Might be hard to answer Tony....
I used lots of 10, 20 and 30sec subs for just a total of 30min through 3 filters for
NGC 3242 but then 16.5hrs of 10min subs for
NGC 3132 (only 3min subs for the RGB)...so not sure there is one answer, I think you can use both normal longish exposures, as well as almost
lucky imaging and of course it depends on the brightness of the subject and sinsitivity of your camera too, you might need to experiment
Good luck, be keen to see how you go
Mike